Transmission of signals for ranging, timing, and data transfer

Abstract

A method is disclosed. In various examples, the method may include receiving an instruction for generating a signal that comprises a ranging signal and a data signal, and transmitting the signal at least partially responsive to the instruction. In various examples the signal may be transmitted via a terrestrial transmitter for transmitting radio waves having encoded messaging information and timing information for one or more of positioning, navigation and timing. In various examples, the signal may include a pulse group comprising a first pulse having a first start time; and a second pulse having a second start time. The second start time may be an integer number of inter-pulse intervals plus an encoding delay after the first start time. The encoding delay may encode data.

What is claimed is: 
     
         1 . A method, comprising:
 receiving an instruction for generating a signal that comprises a ranging signal and a data signal; and   transmitting, via a terrestrial transmitter for transmitting radio waves having encoded messaging information and timing information for one or more of positioning, navigation and timing, the signal at least partially responsive to the instruction, the signal comprising a pulse group comprising:
 a first pulse having a first start time; and 
 a second pulse having a second start time, which is an integer number of inter-pulse intervals plus an encoding delay after the first start time, the encoding delay encoding data. 
   
     
     
         2 . The method of  claim 1 , wherein the integer number is a first integer number and wherein the pulse group comprises a third pulse having a third start time, which is a second integer number of inter-pulse intervals after the first start time. 
     
     
         3 . The method of  claim 2 , wherein the first pulse comprises a first ranging pulse, the third pulse comprises a second ranging pulse, and the second pulse comprises a timing pulse. 
     
     
         4 . The method of  claim 2 , wherein the first pulse comprises a first ranging pulse, the third pulse comprises a second ranging pulse, and the second pulse comprises a data pulse. 
     
     
         5 . The method of  claim 1 , wherein the integer number is a first integer number, wherein the encoding delay is a first encoding delay, and wherein the pulse group comprises a third pulse having a third start time, which is a second integer number of inter-pulse intervals plus a second encoding delay after the first start time. 
     
     
         6 . The method of  claim 5 , wherein the first pulse comprises a first ranging pulse, the second pulse comprises a timing pulse, and the third pulse comprises a data pulse. 
     
     
         7 . The method of  claim 1 , wherein a duration of the inter-pulse intervals is indicative of the terrestrial transmitter. 
     
     
         8 . The method of  claim 7 , comprising:
 receiving a second instruction for generating a second signal; and   transmitting, via a second terrestrial transmitter for transmitting radio waves having encoded messaging information and timing information for one or more of positioning, navigation and timing, the second signal at least partially responsive to the second instruction, the second signal comprising a pulse group comprising:
 a third pulse having a third start time; and 
 a fourth pulse having a fourth start time, which is a further inter-pulse interval after the third start time. 
   
     
     
         9 . The method of  claim 8 , wherein the further inter-pulse interval is different from the inter-pulse intervals and is thereby indicative of the second terrestrial transmitter. 
     
     
         10 . The method of  claim 1 , wherein the pulse group comprises ranging pulses to be used to determine range information and data pulses to encode data, and wherein the ranging pulses and the data pulses are ordered in the pulse group according to a pre-specified pulse-ordering scheme. 
     
     
         11 . The method of  claim 10 , wherein the first pulse is a ranging pulse and the second pulse is a data pulse. 
     
     
         12 . The method of  claim 1 , wherein the pulse group comprises a number of data pulses encoding data and a number of timing pulses encoding timing information, and wherein the number of data pulses and the number of timing pulses are ordered in the pulse group according to a pre-specified pulse-ordering scheme. 
     
     
         13 . The method of  claim 12 , wherein the data is encrypted prior to being encoded in the number of data pulses. 
     
     
         14 . The method of  claim 12 , wherein the data of the number of data pulses includes additional timing information. 
     
     
         15 . The method of  claim 1 , wherein transmitting the signal comprises offsetting a start time of the pulse group by a dithering interval. 
     
     
         16 . The method of  claim 15 , comprising:
 receiving a second instruction for generating a second signal; and   transmitting, via a second terrestrial transmitter, the second signal at least partially responsive to the received second instruction, the second signal exhibiting second pulse groups wherein the second pulse groups exhibit offset start times according to a further dithering interval.   
     
     
         17 . The method of  claim 16 , wherein the dithering interval and the further dithering interval are transmitter-level dithering. 
     
     
         18 . The method of  claim 16 , wherein the dithering interval and the further dithering interval are chain-level dithering. 
     
     
         19 . The method of  claim 16 , wherein the dithering interval and the further dithering interval comprise masking dithering and a dithering interval according to a ramp. 
     
     
         20 . The method of  claim 1 , wherein the pulse group comprises a number of pulses comprising the first pulse and the second pulse wherein respective ones of the number of pulses having either a positive-going phase or a negative-going phase, wherein phases of the respective ones of the number of pulses of the pulse group are according to a pulse-phase signature and the pulse-phase signature is predefined for a broadcast cycle and a terrestrial transmitter. 
     
     
         21 . The method of  claim 20 , wherein the pulse-phase signature comprises an indication of a phase of each of the number of pulses. 
     
     
         22 . The method of  claim 20 , wherein the pulse-phase signature is according to a pre-defined pulse-phase-signature schedule comprising a pulse-phase signature for a number of broadcast cycles. 
     
     
         23 . An apparatus, comprising:
 a controller is to:
 generate an instruction for generating a signal comprising a ranging signal and a data signal, the signal comprising a pulse group comprising:
 a first pulse having a first start time; and 
 a second pulse having a second start time, which is an integer number of inter-pulse intervals plus an encoding delay after the first start time; the encoding delay encoding data; and 
 
 provide the instruction to a terrestrial transmitter for transmitting radio waves having encoded messaging information and timing information for one or more of positioning, navigation and timing.